Raster operations, or ROPs, are binary bitwise operations, such as AND, OR, XOR, and NOT, that are performed on any combination of a destination (D), a source (S), and a pattern (P) object. ROPs are historically used to support transparency and masking in computer printing, screen display, and other graphical environments that do not otherwise support transparency and alpha channels. The use of ROPs may allow the illusion of transparency in a printed document to be achieved via the use of patterned masks.
More recent applications support transparency through other mechanisms than ROPs. Therefore, more modern print drivers, document viewers, and other such applications may not natively support ROPs. However, some applications, such as legacy applications, may still use ROPs. Therefore, the handling of ROPs in documents produced by such applications may present challenges for printer drivers and other such applications that do not natively support ROPs.